Lakhdar Boumia

TISSEMSILT UNIVERSITY · Material sciences

Applying nanofluids in heat transfer systems is an innovative approach to improve the weak thermal characteristics of thermal oils. In this work, the thermal performance of a parabolic trough solar collector using Dowtherm A oil-based nanofluid along with Pd, Au, and NiO nanoparticles as an operating fluid within the receiver tube was numerically i...

The structural, half-metallic, and elastic characteristics of XZrAs (X = Cr, Mn, and V) half-Heusler compounds were theoretically calculated using the WIEN2k code. For the term of the potential exchange and correlation (XC), we calculated structural, electronic, and magnetic properties using the generalized gradient approximation (GGA). The type 1...

The hippocampus is known as one of the most important brain structures since the change in its volume is an early symptom of many diseases such as Alzheimer's disease. Accurate measurement of the hippocampus is very helpful in identifying lesions. Hippocampus segmentation in MRI images is of vital importance for the in-depth study of many brain dis...

Understanding the delicate interplay between geometric design principles and dynamic responses is vital for numerous engineering applications because it allows optimization of structural integrity and performance for manufacturing and special use of this structures. In this study, a complete numerical analysis is undertaken to investigate how diffe...

The aim of this study is to propose a methodology to actively control the vibration of functionally graded plates, with the help of piezoelectric actuators and sensors. The study relays on the classical plate theory to analytically formulate the governing equation of motion, which is then expanded to derive a space state equation of the model. The...

Both electronic as well as magnetic characteristics of Co1-xFexMnSb (x = 0, 0.25, 0.50, 0.75, 1) composite have been studied by employing the first principle (FP) study. The FP calculation was attained using the density functional theory (DFT). The exchange–correlation term has been examined inside the generalized gradient approximation (GGA), as i...

We employed the full-potential linearized augmented plane wave (FP-LAPW) approach to estimate the stability, magneto-electronic, and thermoelectric properties of CrTiRhZ (Z: Al, Si) quaternary Heusler alloys (QHAs) using different exchange–correlation approximations, namely Generalized Gradient Approximation (GGA) and Modified Becke- Johnson (GGA-m...

The primary goal of this study is to develop a mathematical model that predicts the behavior of quadcopters UAV, which are flying robots with four motors. The quadcopters are controlled by three parameters of algorithms known as PID controllers, where P is based on current errors, I is based on the accumulation of previous errors, and D predicts...

The ornithopter-shaped ZK0.1 UAV, which is presented in this paper, is a revolutionary design for an unmanned aerial vehicle (UAV). The movement of the wings is managed by a straightforward system with three driving motors. The whole model was created in SOLIDWORKS, then control blocks were added using the SIMMECHANICS interface after export to...

The present paper presents a new design of an unmanned aerial vehicle (UAV) called ZK0.1, which is an ornithopter. The design uses a simple mechanism with three driving engines to control the wings' movement. The full model was designed in SOLIDWORKS and then exported to MATLAB using SIMMECHANICS interface to add control blocks. A PID controller wa...

The structural, half-metallic, and elastic characteristics of XZrAs (X = Cr, Mn, and V) half-Heusler compounds were theoretically calculated using the WIEN2k code. For the term of the potential exchange and correlation (XC), we calculated structural, electronic, and magnetic properties using the generalized gradient approximation (GGA). The type 1...

The WIEN2k code was used to perform theoretical calculations on the structural, half-metallic, and elastic properties of XZrAs (X = Cr, Mn, and V) half-Heusler compounds. For the term of the potential exchange and correlation (XC), we calculated structural, electronic, and magnetic properties using the generalized gradient approximation. In all com...

Cadmium oxide (CdO) thin films have been successfully deposited on amorphous glass substrates by spray pyrolysis technique at a temperature, 573 °K using aqueous solution of cadmium nitrate 4-Hydrate powder with a concentration of 0.1 M. The X-ray diffraction (XRD) studies have revealed that the films exhibit cubic crystal structure. The modified W...

First-principles calculations based on the density functional theory (DFT) within full-potential linearized augmented plane wave method (FP-LAPW) were carried out to investigate the structural, electronic and magnetic properties of Rh 2 CrZ (Z = Al, Ga, In) Heusler alloys. The electron exchange-correlation energyis described by the generalized grad...

The structural, electronic as well as the magnetic properties of the Co2CrX (X =Al, Ga and In) full-Heusler alloy have been studied using first-principles calculations performed in the framework of density functional theory (DFT) within the generalized gradient approximation (GGA). It was taken into account both possible L21 structures (i.e. Hg2CuT...

In this paper, dynamic properties of a single-walled carbon nanotube (SWCNT) with small scale effects are studied. Based on the nonlocal continuum theory and the Timoshenko beam model, the equations of motion are derived. The influences of scale coefficients, the vibrational mode number, the chirality of carbon nanotube and the aspect ratio on the...

In this paper, a new displacement based high-order shear deformation theory is introduced for the static response of functionally graded sandwich plate. Unlike any other theory, the number of unknown functions involved is only four, as against five in case of other shear deformation theories. The theory presented is variationally consistent, has st...

The thermal effect on wave propagation in double-walled carbon nanotubes (DWNTs) embedded in a polymer matrix is studied in this paper via nonlocal elasticity. The small-scale effects on vibration characteristics of carbon nanotubes are explicitly derived through a complete continuum beam model. In example calculations, the mechanical properties of...

The effect of small size on wave propagation in double-walled carbon nanotubes (DWCNTs) under temperature field is investigated using the Euler–Bernoulli beam model. Dynamic governing equations of the carbon nanotube are formulated on the basis of nonlocal thermal elastic theory. The effects of temperature change and van der Waals forces between th...

This paper is concerned with the use of the nonlocal Timoshenko beam model for free vibration analysis of single-walled carbon nanotubes (CNTs) including the thermal effect. Unlike the Euler beam model, the Timoshenko beam model allows for the effects of transverse shear deformation and rotary inertia. These effects become significant for CNTs with...